The three-dimensional (3D) integration of two or more semiconductor structures can produce a number of benefits to microelectronic applications. For example, 3D integration of microelectronic components can result in improved electrical performance and power consumption while reducing the area of the device foot print. See, for example, P. Garrou, et al., “The Handbook of 3D Integration,” Wiley-VCH (2008).
The 3D integration of semiconductor structures may take place by the attachment of a semiconductor die to one or more additional semiconductor dies (i.e., die-to-die (D2D)), a semiconductor die to one or more semiconductor wafers (i.e., die-to-wafer (D2W)), as well as a semiconductor wafer to one or more additional semiconductor wafers (i.e., wafer-to-wafer (W2W)), or a combination thereof.
Often, the individual semiconductor dies or wafers may be relatively thin and difficult to handle with equipment for processing the dies or wafers. Thus, so-called “carrier” dies or wafers may be attached to the actual dies or wafers that include therein the active and passive components of operative semiconductor devices. The carrier dies or wafers do not typically include any active or passive components of a semiconductor device to be formed. Such carrier dies and wafers are referred to herein as “carrier substrates.” The carrier substrates increase the overall thickness of the dies or wafers and facilitate handling of the dies or wafers by processing equipment used to process the active and/or passive components in the dies or wafers attached thereto that will include the active and passive components of a semiconductor device to be fabricated thereon. Such dies or wafers that include the active and/or passive components of a semiconductor device to be fabricated thereon, or that will ultimately include the active and/or passive components of a semiconductor device to be fabricated thereon upon completion of the manufacturing process, are referred to herein as “device substrates.”
Carrier substrates are typically attached to device substrates using an adhesive. Similar bonding methods may also be used to secure one die or wafer that includes active and/or passive components of one or more semiconductor devices therein to another die or wafer that also includes active and/or passive components of one or more semiconductor devices therein.
The adhesives typically used to bond one die or wafer (e.g., a carrier substrate) to another die or wafer (e.g., a device substrate) may present problems in subsequent processing steps used to fabricate active and/or passive components of one or more semiconductor devices in the dies or wafers.